FIG. 1 illustrates an assembly of two conventional aluminum windows. FIG. 2 illustrates an assembly of four conventional aluminum windows. As shown, it mainly joints the glass frames 20 with the window frames 10 inwardly. While in practical application, this kind of aluminum windows often are set by adopting the forms of side by side or top-down-left-right similar as the glass window curtain. And, the ordinary joint assembling method is to further form a joint bar plate 13 on the vertical frame plate 110 and horizontal frame plate 12 of the window frame 10. While the window frames 10 are left-right side by side assembled, an out laid vertical joint frame plate 30 is formed by jointing the joint bars 13 on the vertical frame plates 110 of these two window frames 10 as a whole. While the window frames 10 adopt the top-down joint assembling, a horizontal joint frame plate 40 is used by jointing the joint bars 13 on the horizontal vertical frame plates 12 of these two window frames 10 together as a whole. Such set up not only requires the extra joint bar 13, but have also the larger volume in the said vertical and horizontal joint frame plates 30, 40. Relatively, the used aluminum material becomes more thus increases the cost. At the same time, because the out laid joint method in the said vertical and horizontal joint plates 30, 40 is adopted, a complex sense of disorder has been created in the whole outside appearance of frames after assembling. This kind of assembling design is thus not an ideal one.
Therefore, it is an object of the present invention to provide an improvement in the aluminum window structure which can obviate and mitigate the above-mentioned drawbacks.